KernelPixels constructor
width × height texels over rgba, four bytes each; zeros when
rgba is not given.
Implementation
KernelPixels(this.width, this.height, {Uint8List? rgba})
: rgba = rgba ?? Uint8List(width * height * 4) {
if (this.rgba.length != width * height * 4) {
throw ArgumentError(
'${this.rgba.length} bytes are not $width × $height RGBA8 texels',
);
}
}